Plant diseases and pests need to be controlled to maintain the quality and quantity of food, feed, and fiber produced by growers around the world. Plant diseases are mainly caused by fungi, bacteria, viruses and nematodes. Plant pests include chewing, sucking and piercing insects from the Lepdoptera, Coleoptera, and Hemiptera, among others. Chemical pesticides are widely used in farming to protect crops from such pests and diseases. These chemical products fight crop pests, diseases, and weeds, resulting in improved yield. Without crop protection and pest control, food production and the quality of food produced would decline. However, the use of chemical pesticides does impose a level of risk as many have properties that can endanger health and the environment if not used properly.
A problem with the continued use of pesticides, herbicides, or other crop protection chemicals is the development of resistance to the control agent. Pesticide resistance is the decreased susceptibility of a pest population to a control agent at doses that once killed most individuals of the species. Therefore, new products are needed with different modes of action to aid in resistance management.
It has long been known that phylogenetically diverse microorganisms can act as natural antagonists of various plant pathogens and pests. Interactions between plant hosts and microorganisms that lead to biocontrol can include antibiosis, competition, induction of host resistance, and predation. Screening and testing isolates have yielded a number of candidates for commercialization. Microbial biopesticides represent an important option for the management of plant diseases and pests. There is a need for biological control agents that are able to compete in field conditions particularly in the presence of herbicides and fungicides that are commonly used in commercial farming and can have antibiotic effects on microorganisms.